Question

Trig help?

Answer 1

What values satisfy the equation?

\(2~\sin~\theta~\cos~\theta+\cos~\theta=0\)

@phi

Answer 2

factor it
cos O(2 sin O + 1) = 0

now its easy

Answer 3

nevermind, I don't think what I just said is right..

Answer 4

no

because we have 2 functions whose product is 0 either one can be 0
so

cos O = 0
and
2sin O + 1 = 0

Answer 5

okay, I know to split it up, now what?

Answer 6

well find the angle whose cos is 0
and sin O = -1/2 so you need the angle whose sine id -1/2

as the required range of values isnt asked for i would find all angles between 0 and 360 degrees

Answer 7

(i typed O for theta)

Answer 8

it's actually between 0 and 2pi XD so you're right

Answer 9

and how do I do that?

Answer 10

they want the answer in radians so find the angles between 0 and 2pi whose cos is 0 from your calculator and in the case of the sine find the angle in the first quadrant whose sine is 1/2. The angles whose sine are negative are in the 3rd and 4th quadrant